Lakes near Talvivaara mining complex serving as drains for sulphate emissions
Two Finnish MEPs appeal to Commission over continued toxic emissions
Lakes near the Talvivaara mining complex in the north-eastern community of Sotkamo will continue to serve as the drainage ditches of sorts for waste water emissions from the installation. Many lakes in tourist areas of Sotkamo and even Upper Savo are threatened by eutrophication and oxygen depletion caused by sulphates from the facility.
The sulphate problem is expected to continue even though the Talvivaara Mining Company says that it has ordered a reverse osmosis water treatment system from a Dutch supplier.
“Sulphate is very difficult to remove. In addition, not all of its harmful effects for nature are fully known”, says Petri Ekholm of the Finnish Environment Institute (SYKE).
Talvivaara is now applying to the Regional State Administrative Agency of Northern Finland for permission to emit waste water with up to 2,000 milligrammes of sulphate per litre.
Under the current licence, the maximum sulphate content for waste water from Talvivaara is just 170 milligrammes per litre, a small fraction of the level in the waste that has been dumped into waterways in the area. The upper limit for drinking water is 250 mg. per litre.
“The company has constantly been operating in violation of its environment permit. A police investigation is still pending”, says Sami Koivula, an environment official at the Regional State Administrative Agency of Northern Finland.
The environmental manager at Talvivaara, Veli-Matti Hilla, denies that the company would have deliberately understated its sulphate emissions. “The large amount of sulphate came as a complete surprise. It was expected to sink to the bottom of the sedimentation pools.
In the early part of the year the flow of waste water into the local waterways was 150 cubic metres an hour. Now this has gone down to 70 cubic metres an hour.
Hilla says that a sulphate content of 2,000 mg. per litre in the waste water would raise the sulphate content in the lakes Nuasjärvi and Laakajärvi to no more than ten mg. per litre, when diluted by the large volume of water in the lakes. “This is average for Finnish lakes”, he says.
“Ten mg. a litre is a high level, and it could be too much in the lakes of the north. Sulphate which accumulates at the bottom can trigger eutrophication and problems with oxygen depletion. That is what has happened in The Netherlands”, says Jouni Lehtoranta, a special researcher at SYKE.
The situation is made worse by the fact that the Talvivaara mine is located in a black shale area, which gives the waters a naturally high level of acidity, including high levels of sulphates and metals.
In lakes near the mine heavier water containing sodium sulphate is concentrated at the bottom, and normal mixing of the layers has not occurred.
“The same phenomenon threatens Lake Laakajärvi. We have performed our own measurements on the lake. According to them there is a layer of heavier water about five metres deep at the bottom where the phosphate level is about 300 mg. per litre”, says hydrologist Veli-Matti Vallinkoski of the Northern Savo Centre for Economic Development, Transport and the Environment.
The lakes of nearby North Savo were not listed among areas of mandatory emission monitoring because the extent of the potential environmental damage was not understood at the time.
Another problem is manganese, which rose to a level considered harmful in a number of nearby lakes.
The environmental problems linked with mining were discussed in Parliament during Thursday’s question time.
Minister of the Environment Ville Niinistö (Green) said that measures taken by the Kainuu Centre for Economic Development, Transport and the Environment led to a decline in emissions from Talvivaara to one fifth of the previous level.
Consequently he said that it has not been necessary to take the measure of shutting down the operation.
The environmental problems linked with the Talvivaara mine have been brought to the attention of the European Commission.
A written question on the matter was submitted to the Commission by two Finnish Members of the European Parliament - Sirpa Pietikäinen (Nat. Coalition Party) and Satu Hassi (Green).
The two MEPs complained that Talvivaara has constantly exceeded its emission limits and has caused extensive damage to waters in the area.
Both say that environmental officials have not efficiently taken issue with the violations, and have thereby violated Finland’s EU obligations.
Previously in HS International Edition:
Emissions from Talvivaara mining complex could hurt Sotkamo tourism (26.4.2012)
Mining raises emotions in Finnish Lapland (10.4.2012)
Sulphate emissions vastly understated in environmental impact study for Talvivaara mine (28.3.2012)
Officials admit failures in oversight of Talvivaara mine (22.11.2011)
Talvivaara press release: Talvivaara Invests More than EUR 13 Million in Environmental Technology